Studies for improving the triboelectric charging property of a toner are actively performed. In particular, for reasons such as environmental consciousness, requirements for more stable chargeability, and production cost, use of a resin having a charge controlling function (charge controlling resin) as a toner raw material has been recently proposed. For example, a toner in which a resin containing a salicylic acid structure is used as a charge controlling resin has been proposed (Patent Literature 1). According to such a method, a toner having an improved sublimation property of salicylic acid and a favorable charging property is obtained.
Recently, demands for a toner that can be fixed at a lower temperature have been increased, and a toner that melts at a low temperature has been developed. On the other hand, due to the effects of global warming, there has also been a demand for an enhancement in storage resistance at a higher temperature and a higher humidity. Under such circumstances, there have been problems that the above charge controlling resin is easily affected by moisture absorption and softening at a high temperature and a high humidity and has a decreased fluidity particularly for use in the toner that melts at a low temperature, and thus there has been room for improvement. Therefore, there has been a demand for developing a toner that can retain sublimation property and favorable charging property and also suppress moisture absorption and softening at a high temperature and a high humidity.
It has also been revealed that charging performance (in particular, charging rise performance at the initial stage) is insufficient in the case where a process speed is made higher in a contact one-component developing system or the like. Against such a phenomenon, there has been a demand for a toner to be quick in rise of charging to a sufficient charge amount in a short time, and there has been a demand for a toner that can achieve the above demand.